In general, link adaptation involves the matching of a modulation scheme, a coding scheme, as well as other signal and/or protocol parameters to the condition of a communications channel between a transmitting device and a receiving device. The matching of the modulation scheme, the coding scheme, as well as the other parameters helps to improve overall communications performance.
In a frequency division duplexed (FDD) communications system, feedback, in the form of a channel quality index (CQI) vector, is provided by a user equipment (UE) to an evolved NodeB (eNB). The CQI vector should be feedback to the eNB at an appropriate frequency so that variations in channel condition are accurately captured. Additionally, the CQI vector can be reported for each resource block group (RBG) for better frequency selective scheduling (FSS) gain.